|War Elephants, Spears||45||12||5||6||Spearmen (2 per howdah)|
|War Elephants, Archers||50||12||5||6||Shortbows (2 per howdah)|
War Elephants: These elephants each have a mahout (driver) and 2 men in an armored howdah (tower). They count as cavalry for most purposes. Spearmen melee as normal (total 2 dice per elephant figure), and archers shoot as normal (total ROF 4 per elephant figure), although they can fire in any direction at will. Elephants themselves melee at 2 dice, bonus 3, damage 2. All melee attacks are halved in non-open terrain or stormy weather; also, archers can still shoot in melee at half-dice (figures in contact only, i.e., at most one rank of elephants).
Design Comments: You'll see that a force like this is a little bit more complicated to handle than other stuff, which is one reason why I didn't want them in the Basic Rules (actually, the mount-with-many-riders is unique and makes them a bit more complex than pretty much anything even in the Advanced Game). The elephant stats are based on the 1E Monster Manual p. 38 (either Asiatic 10HD or African 11HD); and again I think that Gygax went overboard with the attacks there, so I've reduced them to 2 attacks for elephants here (although even that work has a "no more than two" attacks per target rule, which should arguably apply in close-ranked mass combat anyway).
There was some consideration as to exactly how the mechanics of fighting war elephants should work in D&D (can you melee the guys in the tower? does it suffice to just kill the driver?), but ultimately it seemed best to simply apply the BOW standard cavalry rule. I treat elephants as "not naturally aggressive", since there's so many reports of them being frightened off from certain historical battles. Therefore we double the sum riders hit dice (3 men × 1 die each × 2 on mount = 6HD); and this gives at least a chance of their failing a hit-dice-based morale check, as desired (even if it will be a small chance). And elephant figures are presumed to be on some larger base size; my own are 1½×2½ inches (about 40×60mm), but whatever you get yours on is probably okay, too.
The 2 men in each figure-howdah basically act as normal, with the above-noted advantages for archers (note: half-dice missiles in contact are the result of only the front 1:1 howdahs having a shot; and the tactical result, ROF2, is actually the same as they'd get in normal melee, as per spearmen). And the other thing you see here is that if the mount is entirely more powerful than the riders, then we have to track their attacks separately. For example: In a standard melee in open terrain, these figures will roll 2 attack dice each normally for the spearmen, and a further 2 dice with a bonus of +3 each for the elephants, these causing up to 2 hits damage (see MM, taking one-third hit dice for the bonus, and following the 2 dice damage indicated for attacks there as well). This extra damage is capped by the target HD, so it does not apply to enemies with only 1HD (see the BOW Advanced Rules p. 10).
The actual hard part of the design process, setting the price, came last: By adding them to the BookOfWar simulator program and hand-tuning until they were approximately balanced with other basic types, as usual (note: they've been playtested somewhat less than other core types, so pricing is possibly more tentative). Possible further options: Consider giving the elephants themselves heavy armor (total AH6; cost for that armor currently unknown); and possibly force routing elephants to flee in a straight-line-away path only, and attack any friendlies they contact there (try to avoid that at all costs!).
Therefore, if they make sense in your campaign, and you've got the money to spend, these war elephants can make a very powerful addition to your Book of War armies.
(Picture detail from "Schlacht von Zama" by Henri-Paul Motte, circa 1890.)